After visiting your food allergist, you may feel as though you just stepped out of an old Henny Youngman joke: Patient tells his doctor, “It hurts when I do this . . . .” Doctor replies, “Stop doing that.” Much of the medical advice your allergist offers boils down to just that — avoid the foods that ail you.

If you react to peanuts, stop eating them. If you break out in hives whenever you eat fish, order the roast beef, instead. If you get an itchy rash after gulping a glass of milk, stop drinking the stuff. Ahhhh, if only it were that easy. Unfortunately, it’s not, because people don’t eat that way, chefs don’t cook that way, and food manufacturers don’t think that way.

People mix and match foods and spices to create an infinite variety of flavorful foodstuffs. Almost every recipe for a tasty dish calls for several ingredients. Almost every processed food you find on the shelves contains a complex combination of constituents.

To further complicate matters, foods commonly go by several pseudonyms to cloak their true identities. Eggs hide behind labels like “albumin” and “simplesse.” Milk sneaks around as “casein.” Peanuts and soy slip past the guards under the alias of “hydrolyzed vegetable protein.”

You’ve just learned that you’re allergic to one or more foods and that the foods can be hiding in the most unsuspected places. At this point, you probably feel a mix of shock, fear, anxiety, and depression. Your first impulse may be to resign yourself to a lifetime regimen of rice and water and whatever you can manage to grow in your vegetable garden.

I recommend a less radical approach, one that enables you to enjoy a bountiful buffet of foods safely. The first step is to set sensible goals:

Avoid the foods that ail you without avoiding anything you’re not truly allergic to.

Read and understand food labels.

Design a diet that contains a wide variety of foods you love, excludes your allergens, and enables you to maintain proper nutrition while retaining your sanity.

Don’t overdo it. Anxiety may drive you to avoid more foods than necessary. An accurate diagnosis can tell you which foods you’re allergic to, giving you a wider selection of foods you can safely enjoy.

Describing an allergen-free diet as an “avoidance diet” sounds more gloomy than it really is. Sure, you want to avoid the foods that make you sick, but in the process, you often discover a cornucopia of cuisine that pleases your palate and more than satisfies your appetite.

Consider creating an avoidance diet as a quest to discover more exotic foods, to become self-sufficient by cooking your own meals, and to wrest control from an illness that has, up to this point, burdened you with restrictions. Consider it liberating. At this point, you should have an accurate diagnosis in hand.

If you haven’t yet obtained a diagnosis. The diagnosis is key, because it provides you with a list of foods you can’t add to your grocery list. With your list of forbidden fruits (or nuts, milk, fish, or whatever you’re allergic to) and the guidance and information provided later, you’re well equipped to set out on your quest.

Your avoidance diet is unique to you and as varied as you choose to make it. Your goal is to develop a diet with a variety of tasty foods, so that you don’t miss the foods you love . . . at least not much. With that in mind, here are some important suggestions to keep you on track and maximize your food choices:

Design a diet that’s right for you. Create a list of everything you eat or would like to eat that contains the food you’re allergic to, and then carefully seek substitutes based on age, nutritional needs, and tastes. If you love cheese, for example, but are allergic to milk, I’m not about to recommend soy cheese, because most soy cheese contains milk protein, and you may not even find it appetizing. Explore alternatives that you find appealing.

Bolster your buffet. When allergies are limiting your choices, fight back by trying different foods. Just make sure you read the labels carefully before testing the waters.

Be resourceful. Your neighborhood grocery store may not be the best place to explore the multitude of available options. Visit health food stores, online specialty food stores, and stores like Whole Foods and Trader Joe’s.

Hunt for bargains. Healthy foods are typically more pricey than the highly processed foods that crowd the shelves of most grocery stores, so if you’re on a tight budget, you may have to adjust your diet accordingly, clip coupons, and hunt for bargains.

Start cooking. Learning to cook, if you’re not an expert already, can increase your options tenfold while providing you with a new, rewarding hobby. By preparing your own meals from scratch, you can eliminate a host of processed foods from your diet.

When I recommend an avoidance diet to my patients, one of the first questions they ask is “How strict do I need to be?” The short, safe answer is that you need to adhere to the strictest guidelines that you and your doctor establish. I recommend strict avoidance for two reasons:

Strict avoidance limits the risk of reactions. Highly allergic people can experience allergic reactions, even severe and fatal reactions, when exposed to minute amounts of the offending allergen.

Strict avoidance, especially in young children, may improve your chances of outgrowing the allergy.

I recommend strict avoidance of any foods that contain or are at a risk of containing a food that triggers an allergic reaction. However, I realize that all people are different. Work with your doctor to formulate a plan that ensures your desired quality of life while minimizing the risks.

Reading Food Labels

When you’re allergic to a food, every trip to the grocery store is like a clandestine mission to identify and avoid the enemy. Before you step behind enemy lines and walk into your local grocery or convenience store, brief yourself on the following precautionary protocol:

Know all the ways that manufacturers can label the food you’re avoiding, as revealed in the following sections.

Read the ingredients on every package, the warnings, and the fine print.

Re-read the label every time you buy the product. Ingredients can change at any time, and the label does not have to announce “new and improved.”

Master the oddities of food labeling. For example, “dairy free” has nothing to do with being milk free. “Dairy free” refers to the presence of milk fat but not milk protein.

Avoid bulk foods, because they have a higher risk of contamination.

Beware of the deli counter, especially if you have a milk allergy. The worker at the meat counter may use the same slicer for meat and cheese.

Avoiding Egg - When you’re allergic to eggs, a trip to the grocery store can be more challenging than your typical Easter egg hunt. Food labels hide eggs behind a host of names, and can show up as glaze on unlabeled bakery items, as clarifying agents in soups, or as a fat substitute. What do you do when you have a recipe that calls for eggs? Provide a substitute.

Avoiding Milk - Milk morphs into several food products that look nothing like milk, including cheese, butter, sour cream, yogurt, and pudding. It can also show up in a host of foods under an assortment of names.

Avoiding Peanut - In the world of food allergies, peanuts are in a class of their own. They’re extremely allergenic and can cause severe reactions with minimal exposure, so if you’re allergic to peanuts, you need to avoid foods that have even trace elements of the offending food.

Avoiding Soy and Soy Products - Over the years, soybean products have become somewhat of a staple in our diets and the bane of anyone who has an allergy to it. It can hide in everything from the ubiquitous hydrolyzed vegetable protein to tofu and tamari. Studies show that most individuals who have a soy allergy can safely eat soy lecithin and soy oil, but check with your doctor before you decide to indulge.

Avoiding Nuts - Like peanuts, tree nuts can cause severe reactions with minimal exposure. If you have a tree nut allergy, you’re likely to be allergic to several but not all tree nuts, but avoidance is most effective if you avoid all tree nuts.

Avoiding Wheat - For most people in the West, wheat is the bread of life. For those who have wheat allergies, however, wheat and the many food products that contain it are pesky troublemakers that are tough to spot

Avoiding Fish - When you’ve been diagnosed as having an allergy to fish, your first question is likely to be: “Which fish? Cod? Salmon? Sturgeon? Freshwater? Saltwater?” Although all fish are not created equal, most people who have a fish allergy are allergic to several types of fish, so I generally recommend that if you’re allergic to one type, avoid them all — both freshwater and saltwater varieties, canned, fresh, sushi, you name it.

Allergic reactions to fish and shellfish can be severe and are often a cause of anaphylaxis, so if you’re allergic to fish, be prepared to identify and avoid them. Although canned fish tend to be less of a problem, avoid canned fish, as well, unless your doctor instructs you that a specific fish is okay for you to eat.

Avoiding Shellfish - Shellfish are notorious for triggering severe allergic reactions and even anaphylaxis. If you’re allergic to shellfish, you already know to avoid shellfish at home, but you should also remain aware of any risks from eating out and any hidden sources of shellfish.

Avoiding Sesame - Sesame is becoming increasingly popular in Western diet and increasingly a problem for those who are allergic to it. Sesame seeds contain extremely potent allergens and can cause severe allergic reactions and anaphylaxis.

Although the sesame allergy gets less press than peanut and shellfish allergies, allergic reactions to sesame can be just as severe. Because sesame is such a versatile food, it can show up in a host of unsuspected places. Sesame can show up in non-sesame products, especially bread, due to crosscontamination from other bakery items that use sesame.

More and more food manufacturers are sticking precautionary labels on their packaging. You pick up a granola bar, and it says, “May contain peanuts.” You’d think that the people making the granola bar would know if they put peanuts in it, but apparently they forgot.

More of these precautions are showing up since FALCPA was passed, and I can speculate on only three reasons for this increase:

Changes in manufacturing processes have introduced more opportunities for cross-contamination. (Machines used to produce a food that contains common allergens is used to produce food that doesn’t.)

Companies are becoming more allergy aware and conscientious in their labeling.

Manufacturers are covering their posteriors to adhere to the new laws, even though FALCPA doesn’t require it, contrary to popular belief.

The problem with these umbrella precautions is that they often and unnecessarily increase the anxiety of those who suffer from food allergies, and they slap additional restrictions on diets. They end up warning consumers of food items that are perfectly safe and add confusion and uncertainty to a labeling system that’s sufficiently confusing.

In the following sections, I translate these precautions into plain English, identify the ones that suggest the greatest risk, and caution you to avoid the common mistake of assuming that just because you haven’t reacted to a particular item in the past you won’t react to it this time.

“This product may contain . . .”

Manufacturers often label products with cryptic precautions, such as “This product may contain . . .” or “Produced on shared equipment” or “Product may contain traces of . . . .” These phrases can signal anything from a nonexistent to a serious risk, so you have no choice but to take them seriously.

Such precautions usually indicate that the manufacturer produces more than one product on a single machine, as described in the following scenarios:

Scenario 1: A peanut product and a non-peanut product are produced on separate equipment, but the company says that if the peanut butter cookie line breaks down, they could start to make those cookies on the vanilla cream cookie equipment. This may never happen but the label appears anyway because of that theoretical possibility.

Scenario 2: A peanut and a non-peanut product are produced on the same equipment but the equipment is thoroughly cleaned before switching from one product to the other. Some products may be more amenable to cleaning than others. A liquid food (ice cream is a great example) is quite easy to clean as long as sufficient care is taken. Dry products (cereals, crackers, cookies) may be harder to completely remove from machinery.

Scenario 3: A peanut and a non-peanut candy are produced on shared equipment and no cleaning is done between runs. This could be deadly!

In the end, you can’t truly know what these precautionary words mean, so you have to avoid any products that contain these vague warnings. Virtually no ice cream is made on dedicated, peanut-free equipment, but most ice cream from large manufacturers is likely to be safe, whereas ice cream from small companies is commonly contaminated, often with no warning on the label.

“Produced in a facility . . .”

Slightly less vague than “This package may contain . . .” is any precautionary label indicating that the product was made in a facility that produces another product that contains a common allergen. In some cases, the facility may manufacture the two products a quarter mile away from each other.

The products may not even cross paths until they reach the distribution center, in packages, which is really no different from how they meet at the grocery store. That doesn’t mean you should ignore the precaution. It’s not worth the risk, so the best recourse is to simply pass on such products and avoid them all.

If you have a serious craving for the food and can’t track down a safer alternative, then give the manufacturer a call and ask for details. Always err on the safe side when it comes to precautionary labels. Risks of cross-contamination are certainly less with large companies than with smaller ones, but you should always check with the manufacturer to be sure.

For lifelong label readers like me, the recent flood of precautionary labels has become an enormous source of frustration. Prior to the late 1990s these precautions were as rare as a bag of peanuts at a food allergy seminar. Now they’re cropping up on the labels of the most innocuous foods.

And the worst part of it is that they’re starting to show up on lots of stuff I used to love to eat! So, what’s a food allergy sufferer to do? You have no choice — once the precaution appears, the product is off limits. As soon as the manufacturer splashes this warning on a product, the company is perfectly free to stop cleaning its equipment.

A product that was previously safe may now pose a deadly risk. Say you ate a couple candy bars before noticing the new precautionary warning, and they didn’t make you sick. Can you safely assume that the warning is bogus and you’re free to continue consuming the product without a care in the world? Nope.

Even if you haven’t reacted to the product, yet, continuing to consume it places you at risk. Why? Here are two good reasons:

First, the company may have changed the way it cleans its equipment, especially now that it has a warning on the label that protects it.

Second (and more importantly), the nature of contaminated food is entirely inconsistent. For example, if the plant produces a non-peanut candy after producing a peanut candy on the same equipment, the first 100 bags of non-peanut product may be loaded with peanut, while the next 100 have less, and the last 10,000 have none. Eating this candy is like playing Russian roulette — you may get away with it the first 49 times and then get burned by bag 50.

Nutritional Needs

Avoidance diets are like being caught between a rock and a hard place, especially with some of the major food allergens like milk, egg, and wheat, that comprise such a large part of our diets. You may not be able to eat one or more of these foods because they make you sick, but if you don’t eat them you risk becoming malnourished.

To remain healthy, work with your doctor to devise a strategy that meets your nutritional needs while ensuring that you avoid the foods that trigger reactions. This is especially true for infants and young children and for certain specific nutritional requirements, including calcium.

Improper nutrition, especially during the early years of development, can lead to serious health problems, including weight loss, poor growth, and weak bones. It may even affect brain development in young children.

Because milk and milk-based formulas are the most serious concerns during the early stages of development, the examples we provide in the following sections focus primarily on nutritional issues that arise when infants and children must avoid milk.

From birth up to approximately two years of age, infants require a diet rich in fat and protein, so a milk-free diet can be particularly risky for infants. Failing to meet the minimum requirements for fat, protein, calcium, vitamins, and other nutrients can have serious long-term consequences, even the loss of IQ points, so finding a suitable replacement is essential.

The following list offers a few options along with important points to keep in mind when searching for a solution:

Breast feeding is best, although in some instances the mother must avoid foods in her diet that the baby is allergic to.

If breast feeding is not an option, use an infant formula that doesn’t contain cow’s milk. Alternatives to cow’s milk formulas, including soy and extensively hydrolyzed formulas, may be appropriate alternatives to breast milk.

Breast feeding or a suitable infant formula may be needed up to 18 to 24 months of age to ensure adequate intake of fat, protein, calcium, and vitamins.

Soy is often a good substitute, but many infants who are allergic to milk are allergic to soy.

Rice milk is not an adequate substitute.

If you have questions or concerns, consult a nutritionist, no matter what the age of the child.

Toddler With Milk Allergy

After age two or three, meeting a child’s nutritional needs gets a little easier, at least theoretically. As a toddler, the child is more capable of ingesting and digesting a wider variety of foods. That’s the easy part. The tough part is that toddlers are more capable of resisting your efforts to keep they away from the foods that make them sick, and they’re generally pickier about the foods they choose to eat.

Toddlers still require lots of protein, but their fat needs become easier to meet. (Most pediatricians normally switch a child without food allergies from whole milk to a milk with a lower fat content at age two.) The approach for meeting the vitamin needs of a toddler with food allergies is much the same as meeting the needs of a toddler without food allergies — the child should eat a variety and a sufficient amount of fruits and vegetables.

For toddlers with milk allergy, getting enough calcium is especially challenging. Try the following options until you find something that your child likes or at least doesn’t fuss about too much:

Milk substitutes, such as soy milk or rice milk (rice milk is okay for older kids, because they can get their protein from other sources)

Calcium-fortified juices, such as orange juice with calcium

Calcium supplements

How much calcium does a toddler need? About 600 mg of calcium per day. Fortified juices typically have 200 to 300 mg per cup, but don’t count on the label to tell you that. Labels typically express the amount of calcium in percentages, not milligrams, where 100 percent equals an outdated adult recommended daily dose of 1,000 mg (the current recommendation is 1300 mg for adults).

Some people think they can eat enough green vegetables to meet calcium needs but you would literally need to eat a head of broccoli daily to accomplish this. Getting a sufficient amount of calcium is critical for development and health, so keep trying different sources of calcium until you hit on something that your child can live with.

Follow the average kid around for a day and watch what he eats, and you get a pretty clear idea of the challenges you can expect when trying to meet the nutritional needs of a child or adolescent, even one who doesn’t have a food allergy.

At this stage, you either have an ally who’s ready to take on more responsibility for taking care of herself and meeting her own nutritional needs or a child who prefers a more liberal lifestyle with lousy eating habits and a penchant for increased risk taking — cheating on the diet. Guess which one is more common. Later, I'll discuss the challenges in greater detail and provide tips on how to effectively overcome them . . . with the assistance of your child, of course.

As an adult, you’re capable of attending to your own nutritional needs, so I won’t lecture you on the benefits of a varied diet, including plenty of fruits and vegetables that you’re not allergic to. I will, however, stress the importance of getting your RDA of calcium. By weight, calcium is one of the most plentiful minerals in the human body, accounting for 1.5 percent to 2 percent of body weight.

And, as the milk commercials claim, it builds strong teeth and bones. The average adult requires about 1,300 milligrams of calcium, and people who don’t have a milk allergy have little problem meeting this goal through a variety of milk products, including milk, cheese, yogurt, and ice cream. When you’re on a milk-free diet, however, you need to explore other sources:

Milk substitutes, such as soy milk or rice milk

Calcium-fortified juices, such as orange juice with calcium Calcium supplements.

Rotation Diet

Unlike an avoidance diet, which calls for the elimination of offending foods from your diet, a rotation diet allows you to eat some of the food some of the time. In other words, you limit the amount of the food that causes problems, but you don’t completely eliminate it.

For example, you may consume a tolerable amount of milk products, once or twice a week. Sounds good, huh? Well, it is good for some people — mostly for people with food intolerances rather than true food allergies.

Food intolerances tend to be much more dose-related than food allergies, which can often be triggered by exposure to a very small amount of the problem food. Only by consulting with your doctor can you decide whether a rotation diet may be right for you.

Consult your doctor and get permission before attempting any sort of rotation diet, and check in regularly with your doctor. Your doctor may need to adjust your diet over time, as the food allergies may fluctuate in either direction.

If you have a severe food allergy, I have one word of advice about trying a rotation diet: forget-about-it. Nobody with a serious food allergy or a risk of anaphylaxis should attempt it. It’s just too risky. Consider it only if you meet all four of the following conditions:

Your food allergy is mild.

Your doctor tells you that you’re at absolutely no risk of experiencing anaphylaxis.

Your doctor gives you permission.

Your doctor creates and monitors your diet, and you check in regularly for any necessary modifications.

An effective rotation diet is like a good golf swing. It requires a careful backswing, a smooth forward stroke, and an effective follow-through:

Backswing: Plan in advance so you know exactly how much of each food you can eat on which days. Keep a calendar or food diary.

Forward stroke: Follow your calendar, and don’t try to fudge on the amounts of food you eat or the days on which you eat them.

Follow-through: Log the foods you eat and note how you feel after eating them (on your calendar or food diary), and check with your doctor regularly to make necessary adjustments. In some cases, your doctor may need to do follow-up allergy tests to ensure that increased exposure to certain foods is not worsening your allergies.